U.S. patent application Ser. Nos. 10/429,930 and 10/429,932 are generally directed towards the concept of computer systems having auxiliary processing and auxiliary mechanisms that provide some auxiliary computing functionality. For example, a small LCD on the lid or side of a laptop computer can provide its owner with useful information, such as a meeting location and time, even when the main computer display is not easily visible, such as when a laptop computer's lid is closed and/or the main computer is powered down. Controls such as buttons may be provided to allow the user to interact with the auxiliary device to view different types of data, such as to view additional appointments among calendar data, read email messages, read directions, play media, and so forth.
Somewhat similar to an auxiliary LCD screen built into a mobile host computer, a mobile telephone, a music playing device, a pocket-sized personal computer, a personal digital assistant and so forth can serve as an auxiliary device to a main computer when coupled to it physically and/or via a wireless (e.g., Bluetooth or infrared) link, as long as the device is programmed to allow its display and/or other functionality to be used with data originating at the main computer system. In general, any device with I/O capabilities that can interface in virtually any way with a computer system can potentially serve as an auxiliary computing device.
One significant advantage to having an auxiliary device for a main computer system is that some information may be made available even while the main computer is fully turned off or is within one of various sleep states, (e.g., possibly those sleep states standardized by the ACPI, or Advanced Configuration and Power Interface, specification). To understand why this is advantageous, consider that when the main computer is operating, a significant amount of power is consumed. Power consumption is a significant issue when dealing with mobile personal computers such as laptops and tablet-based computing devices, because users desire long battery life between recharges. In general, the longer the PC is in a fully-powered state (e.g., corresponding to S0 in ACPI), the shorter the battery life. An auxiliary device conserves power by allowing the user to leave the main computer off when accessing certain types of information. Other benefits of auxiliary displays include rapid access to information, e.g., a laptop does not have to have its lid opened to present a user with information, exit a sleep state, spin up a disk and so forth.
However, an auxiliary device associated with a main computer that is not fully-powered is limited to operating with data cached from the last time the main computer system was on and/or any data obtained independent of the main computer system. As a result, the cached data may be stale, and/or the cached data may be insufficient for some task the user wants to perform, such as because of limited memory on the auxiliary device. What is needed is a way for an auxiliary device to access data from the main computer system, while doing so in a manner that conserves the power of the main computer system.